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1'use strict';
2const common = require('../common');
3const assert = require('assert');
4
5const b = Buffer.from('abcdef');
6const buf_a = Buffer.from('a');
7const buf_bc = Buffer.from('bc');
8const buf_f = Buffer.from('f');
9const buf_z = Buffer.from('z');
10const buf_empty = Buffer.from('');
11
12const s = 'abcdef';
13
14assert.strictEqual(b.indexOf('a'), 0);
15assert.strictEqual(b.indexOf('a', 1), -1);
16assert.strictEqual(b.indexOf('a', -1), -1);
17assert.strictEqual(b.indexOf('a', -4), -1);
18assert.strictEqual(b.indexOf('a', -b.length), 0);
19assert.strictEqual(b.indexOf('a', NaN), 0);
20assert.strictEqual(b.indexOf('a', -Infinity), 0);
21assert.strictEqual(b.indexOf('a', Infinity), -1);
22assert.strictEqual(b.indexOf('bc'), 1);
23assert.strictEqual(b.indexOf('bc', 2), -1);
24assert.strictEqual(b.indexOf('bc', -1), -1);
25assert.strictEqual(b.indexOf('bc', -3), -1);
26assert.strictEqual(b.indexOf('bc', -5), 1);
27assert.strictEqual(b.indexOf('bc', NaN), 1);
28assert.strictEqual(b.indexOf('bc', -Infinity), 1);
29assert.strictEqual(b.indexOf('bc', Infinity), -1);
30assert.strictEqual(b.indexOf('f'), b.length - 1);
31assert.strictEqual(b.indexOf('z'), -1);
32assert.strictEqual(b.indexOf(''), 0);
33assert.strictEqual(b.indexOf('', 1), 1);
34assert.strictEqual(b.indexOf('', b.length + 1), b.length);
35assert.strictEqual(b.indexOf('', Infinity), b.length);
36assert.strictEqual(b.indexOf(buf_a), 0);
37assert.strictEqual(b.indexOf(buf_a, 1), -1);
38assert.strictEqual(b.indexOf(buf_a, -1), -1);
39assert.strictEqual(b.indexOf(buf_a, -4), -1);
40assert.strictEqual(b.indexOf(buf_a, -b.length), 0);
41assert.strictEqual(b.indexOf(buf_a, NaN), 0);
42assert.strictEqual(b.indexOf(buf_a, -Infinity), 0);
43assert.strictEqual(b.indexOf(buf_a, Infinity), -1);
44assert.strictEqual(b.indexOf(buf_bc), 1);
45assert.strictEqual(b.indexOf(buf_bc, 2), -1);
46assert.strictEqual(b.indexOf(buf_bc, -1), -1);
47assert.strictEqual(b.indexOf(buf_bc, -3), -1);
48assert.strictEqual(b.indexOf(buf_bc, -5), 1);
49assert.strictEqual(b.indexOf(buf_bc, NaN), 1);
50assert.strictEqual(b.indexOf(buf_bc, -Infinity), 1);
51assert.strictEqual(b.indexOf(buf_bc, Infinity), -1);
52assert.strictEqual(b.indexOf(buf_f), b.length - 1);
53assert.strictEqual(b.indexOf(buf_z), -1);
54assert.strictEqual(b.indexOf(buf_empty), 0);
55assert.strictEqual(b.indexOf(buf_empty, 1), 1);
56assert.strictEqual(b.indexOf(buf_empty, b.length + 1), b.length);
57assert.strictEqual(b.indexOf(buf_empty, Infinity), b.length);
58assert.strictEqual(b.indexOf(0x61), 0);
59assert.strictEqual(b.indexOf(0x61, 1), -1);
60assert.strictEqual(b.indexOf(0x61, -1), -1);
61assert.strictEqual(b.indexOf(0x61, -4), -1);
62assert.strictEqual(b.indexOf(0x61, -b.length), 0);
63assert.strictEqual(b.indexOf(0x61, NaN), 0);
64assert.strictEqual(b.indexOf(0x61, -Infinity), 0);
65assert.strictEqual(b.indexOf(0x61, Infinity), -1);
66assert.strictEqual(b.indexOf(0x0), -1);
67
68// test offsets
69assert.strictEqual(b.indexOf('d', 2), 3);
70assert.strictEqual(b.indexOf('f', 5), 5);
71assert.strictEqual(b.indexOf('f', -1), 5);
72assert.strictEqual(b.indexOf('f', 6), -1);
73
74assert.strictEqual(b.indexOf(Buffer.from('d'), 2), 3);
75assert.strictEqual(b.indexOf(Buffer.from('f'), 5), 5);
76assert.strictEqual(b.indexOf(Buffer.from('f'), -1), 5);
77assert.strictEqual(b.indexOf(Buffer.from('f'), 6), -1);
78
79assert.strictEqual(Buffer.from('ff').indexOf(Buffer.from('f'), 1, 'ucs2'), -1);
80
81// Test invalid and uppercase encoding
82assert.strictEqual(b.indexOf('b', 'utf8'), 1);
83assert.strictEqual(b.indexOf('b', 'UTF8'), 1);
84assert.strictEqual(b.indexOf('62', 'HEX'), 1);
85assert.throws(() => b.indexOf('bad', 'enc'), /Unknown encoding: enc/);
86
87// test hex encoding
88assert.strictEqual(
89  Buffer.from(b.toString('hex'), 'hex')
90    .indexOf('64', 0, 'hex'),
91  3
92);
93assert.strictEqual(
94  Buffer.from(b.toString('hex'), 'hex')
95    .indexOf(Buffer.from('64', 'hex'), 0, 'hex'),
96  3
97);
98
99// Test base64 encoding
100assert.strictEqual(
101  Buffer.from(b.toString('base64'), 'base64')
102    .indexOf('ZA==', 0, 'base64'),
103  3
104);
105assert.strictEqual(
106  Buffer.from(b.toString('base64'), 'base64')
107    .indexOf(Buffer.from('ZA==', 'base64'), 0, 'base64'),
108  3
109);
110
111// test ascii encoding
112assert.strictEqual(
113  Buffer.from(b.toString('ascii'), 'ascii')
114    .indexOf('d', 0, 'ascii'),
115  3
116);
117assert.strictEqual(
118  Buffer.from(b.toString('ascii'), 'ascii')
119    .indexOf(Buffer.from('d', 'ascii'), 0, 'ascii'),
120  3
121);
122
123// Test latin1 encoding
124assert.strictEqual(
125  Buffer.from(b.toString('latin1'), 'latin1')
126    .indexOf('d', 0, 'latin1'),
127  3
128);
129assert.strictEqual(
130  Buffer.from(b.toString('latin1'), 'latin1')
131    .indexOf(Buffer.from('d', 'latin1'), 0, 'latin1'),
132  3
133);
134assert.strictEqual(
135  Buffer.from('aa\u00e8aa', 'latin1')
136    .indexOf('\u00e8', 'latin1'),
137  2
138);
139assert.strictEqual(
140  Buffer.from('\u00e8', 'latin1')
141    .indexOf('\u00e8', 'latin1'),
142  0
143);
144assert.strictEqual(
145  Buffer.from('\u00e8', 'latin1')
146    .indexOf(Buffer.from('\u00e8', 'latin1'), 'latin1'),
147  0
148);
149
150// Test binary encoding
151assert.strictEqual(
152  Buffer.from(b.toString('binary'), 'binary')
153    .indexOf('d', 0, 'binary'),
154  3
155);
156assert.strictEqual(
157  Buffer.from(b.toString('binary'), 'binary')
158    .indexOf(Buffer.from('d', 'binary'), 0, 'binary'),
159  3
160);
161assert.strictEqual(
162  Buffer.from('aa\u00e8aa', 'binary')
163    .indexOf('\u00e8', 'binary'),
164  2
165);
166assert.strictEqual(
167  Buffer.from('\u00e8', 'binary')
168    .indexOf('\u00e8', 'binary'),
169  0
170);
171assert.strictEqual(
172  Buffer.from('\u00e8', 'binary')
173    .indexOf(Buffer.from('\u00e8', 'binary'), 'binary'),
174  0
175);
176
177
178// Test optional offset with passed encoding
179assert.strictEqual(Buffer.from('aaaa0').indexOf('30', 'hex'), 4);
180assert.strictEqual(Buffer.from('aaaa00a').indexOf('3030', 'hex'), 4);
181
182{
183  // Test usc2 and utf16le encoding
184  ['ucs2', 'utf16le'].forEach((encoding) => {
185    const twoByteString = Buffer.from(
186      '\u039a\u0391\u03a3\u03a3\u0395', encoding);
187
188    assert.strictEqual(twoByteString.indexOf('\u0395', 4, encoding), 8);
189    assert.strictEqual(twoByteString.indexOf('\u03a3', -4, encoding), 6);
190    assert.strictEqual(twoByteString.indexOf('\u03a3', -6, encoding), 4);
191    assert.strictEqual(twoByteString.indexOf(
192      Buffer.from('\u03a3', encoding), -6, encoding), 4);
193    assert.strictEqual(-1, twoByteString.indexOf('\u03a3', -2, encoding));
194  });
195}
196
197const mixedByteStringUcs2 =
198    Buffer.from('\u039a\u0391abc\u03a3\u03a3\u0395', 'ucs2');
199assert.strictEqual(mixedByteStringUcs2.indexOf('bc', 0, 'ucs2'), 6);
200assert.strictEqual(mixedByteStringUcs2.indexOf('\u03a3', 0, 'ucs2'), 10);
201assert.strictEqual(-1, mixedByteStringUcs2.indexOf('\u0396', 0, 'ucs2'));
202
203assert.strictEqual(
204  mixedByteStringUcs2.indexOf(Buffer.from('bc', 'ucs2'), 0, 'ucs2'), 6);
205assert.strictEqual(
206  mixedByteStringUcs2.indexOf(Buffer.from('\u03a3', 'ucs2'), 0, 'ucs2'), 10);
207assert.strictEqual(
208  -1, mixedByteStringUcs2.indexOf(Buffer.from('\u0396', 'ucs2'), 0, 'ucs2'));
209
210{
211  const twoByteString = Buffer.from('\u039a\u0391\u03a3\u03a3\u0395', 'ucs2');
212
213  // Test single char pattern
214  assert.strictEqual(twoByteString.indexOf('\u039a', 0, 'ucs2'), 0);
215  let index = twoByteString.indexOf('\u0391', 0, 'ucs2');
216  assert.strictEqual(index, 2, `Alpha - at index ${index}`);
217  index = twoByteString.indexOf('\u03a3', 0, 'ucs2');
218  assert.strictEqual(index, 4, `First Sigma - at index ${index}`);
219  index = twoByteString.indexOf('\u03a3', 6, 'ucs2');
220  assert.strictEqual(index, 6, `Second Sigma - at index ${index}`);
221  index = twoByteString.indexOf('\u0395', 0, 'ucs2');
222  assert.strictEqual(index, 8, `Epsilon - at index ${index}`);
223  index = twoByteString.indexOf('\u0392', 0, 'ucs2');
224  assert.strictEqual(-1, index, `Not beta - at index ${index}`);
225
226  // Test multi-char pattern
227  index = twoByteString.indexOf('\u039a\u0391', 0, 'ucs2');
228  assert.strictEqual(index, 0, `Lambda Alpha - at index ${index}`);
229  index = twoByteString.indexOf('\u0391\u03a3', 0, 'ucs2');
230  assert.strictEqual(index, 2, `Alpha Sigma - at index ${index}`);
231  index = twoByteString.indexOf('\u03a3\u03a3', 0, 'ucs2');
232  assert.strictEqual(index, 4, `Sigma Sigma - at index ${index}`);
233  index = twoByteString.indexOf('\u03a3\u0395', 0, 'ucs2');
234  assert.strictEqual(index, 6, `Sigma Epsilon - at index ${index}`);
235}
236
237const mixedByteStringUtf8 = Buffer.from('\u039a\u0391abc\u03a3\u03a3\u0395');
238assert.strictEqual(mixedByteStringUtf8.indexOf('bc'), 5);
239assert.strictEqual(mixedByteStringUtf8.indexOf('bc', 5), 5);
240assert.strictEqual(mixedByteStringUtf8.indexOf('bc', -8), 5);
241assert.strictEqual(mixedByteStringUtf8.indexOf('\u03a3'), 7);
242assert.strictEqual(mixedByteStringUtf8.indexOf('\u0396'), -1);
243
244
245// Test complex string indexOf algorithms. Only trigger for long strings.
246// Long string that isn't a simple repeat of a shorter string.
247let longString = 'A';
248for (let i = 66; i < 76; i++) {  // from 'B' to 'K'
249  longString = longString + String.fromCharCode(i) + longString;
250}
251
252const longBufferString = Buffer.from(longString);
253
254// Pattern of 15 chars, repeated every 16 chars in long
255let pattern = 'ABACABADABACABA';
256for (let i = 0; i < longBufferString.length - pattern.length; i += 7) {
257  const index = longBufferString.indexOf(pattern, i);
258  assert.strictEqual((i + 15) & ~0xf, index,
259                     `Long ABACABA...-string at index ${i}`);
260}
261
262let index = longBufferString.indexOf('AJABACA');
263assert.strictEqual(index, 510, `Long AJABACA, First J - at index ${index}`);
264index = longBufferString.indexOf('AJABACA', 511);
265assert.strictEqual(index, 1534, `Long AJABACA, Second J - at index ${index}`);
266
267pattern = 'JABACABADABACABA';
268index = longBufferString.indexOf(pattern);
269assert.strictEqual(index, 511, `Long JABACABA..., First J - at index ${index}`);
270index = longBufferString.indexOf(pattern, 512);
271assert.strictEqual(
272  index, 1535, `Long JABACABA..., Second J - at index ${index}`);
273
274// Search for a non-ASCII string in a pure ASCII string.
275const asciiString = Buffer.from(
276  'arglebargleglopglyfarglebargleglopglyfarglebargleglopglyf');
277assert.strictEqual(-1, asciiString.indexOf('\x2061'));
278assert.strictEqual(asciiString.indexOf('leb', 0), 3);
279
280// Search in string containing many non-ASCII chars.
281const allCodePoints = [];
282for (let i = 0; i < 65534; i++) allCodePoints[i] = i;
283const allCharsString = String.fromCharCode.apply(String, allCodePoints) +
284    String.fromCharCode(65534, 65535);
285const allCharsBufferUtf8 = Buffer.from(allCharsString);
286const allCharsBufferUcs2 = Buffer.from(allCharsString, 'ucs2');
287
288// Search for string long enough to trigger complex search with ASCII pattern
289// and UC16 subject.
290assert.strictEqual(-1, allCharsBufferUtf8.indexOf('notfound'));
291assert.strictEqual(-1, allCharsBufferUcs2.indexOf('notfound'));
292
293// Needle is longer than haystack, but only because it's encoded as UTF-16
294assert.strictEqual(Buffer.from('aaaa').indexOf('a'.repeat(4), 'ucs2'), -1);
295
296assert.strictEqual(Buffer.from('aaaa').indexOf('a'.repeat(4), 'utf8'), 0);
297assert.strictEqual(Buffer.from('aaaa').indexOf('你好', 'ucs2'), -1);
298
299// Haystack has odd length, but the needle is UCS2.
300assert.strictEqual(Buffer.from('aaaaa').indexOf('b', 'ucs2'), -1);
301
302{
303  // Find substrings in Utf8.
304  const lengths = [1, 3, 15];  // Single char, simple and complex.
305  const indices = [0x5, 0x60, 0x400, 0x680, 0x7ee, 0xFF02, 0x16610, 0x2f77b];
306  for (let lengthIndex = 0; lengthIndex < lengths.length; lengthIndex++) {
307    for (let i = 0; i < indices.length; i++) {
308      const index = indices[i];
309      let length = lengths[lengthIndex];
310
311      if (index + length > 0x7F) {
312        length = 2 * length;
313      }
314
315      if (index + length > 0x7FF) {
316        length = 3 * length;
317      }
318
319      if (index + length > 0xFFFF) {
320        length = 4 * length;
321      }
322
323      const patternBufferUtf8 = allCharsBufferUtf8.slice(index, index + length);
324      assert.strictEqual(index, allCharsBufferUtf8.indexOf(patternBufferUtf8));
325
326      const patternStringUtf8 = patternBufferUtf8.toString();
327      assert.strictEqual(index, allCharsBufferUtf8.indexOf(patternStringUtf8));
328    }
329  }
330}
331
332{
333  // Find substrings in Usc2.
334  const lengths = [2, 4, 16];  // Single char, simple and complex.
335  const indices = [0x5, 0x65, 0x105, 0x205, 0x285, 0x2005, 0x2085, 0xfff0];
336  for (let lengthIndex = 0; lengthIndex < lengths.length; lengthIndex++) {
337    for (let i = 0; i < indices.length; i++) {
338      const index = indices[i] * 2;
339      const length = lengths[lengthIndex];
340
341      const patternBufferUcs2 =
342          allCharsBufferUcs2.slice(index, index + length);
343      assert.strictEqual(
344        index, allCharsBufferUcs2.indexOf(patternBufferUcs2, 0, 'ucs2'));
345
346      const patternStringUcs2 = patternBufferUcs2.toString('ucs2');
347      assert.strictEqual(
348        index, allCharsBufferUcs2.indexOf(patternStringUcs2, 0, 'ucs2'));
349    }
350  }
351}
352
353[
354  () => {},
355  {},
356  [],
357].forEach((val) => {
358  assert.throws(
359    () => b.indexOf(val),
360    {
361      code: 'ERR_INVALID_ARG_TYPE',
362      name: 'TypeError',
363      message: 'The "value" argument must be one of type number or string ' +
364               'or an instance of Buffer or Uint8Array.' +
365               common.invalidArgTypeHelper(val)
366    }
367  );
368});
369
370// Test weird offset arguments.
371// The following offsets coerce to NaN or 0, searching the whole Buffer
372assert.strictEqual(b.indexOf('b', undefined), 1);
373assert.strictEqual(b.indexOf('b', {}), 1);
374assert.strictEqual(b.indexOf('b', 0), 1);
375assert.strictEqual(b.indexOf('b', null), 1);
376assert.strictEqual(b.indexOf('b', []), 1);
377
378// The following offset coerces to 2, in other words +[2] === 2
379assert.strictEqual(b.indexOf('b', [2]), -1);
380
381// Behavior should match String.indexOf()
382assert.strictEqual(
383  b.indexOf('b', undefined),
384  s.indexOf('b', undefined));
385assert.strictEqual(
386  b.indexOf('b', {}),
387  s.indexOf('b', {}));
388assert.strictEqual(
389  b.indexOf('b', 0),
390  s.indexOf('b', 0));
391assert.strictEqual(
392  b.indexOf('b', null),
393  s.indexOf('b', null));
394assert.strictEqual(
395  b.indexOf('b', []),
396  s.indexOf('b', []));
397assert.strictEqual(
398  b.indexOf('b', [2]),
399  s.indexOf('b', [2]));
400
401// All code for handling encodings is shared between Buffer.indexOf and
402// Buffer.lastIndexOf, so only testing the separate lastIndexOf semantics.
403
404// Test lastIndexOf basic functionality; Buffer b contains 'abcdef'.
405// lastIndexOf string:
406assert.strictEqual(b.lastIndexOf('a'), 0);
407assert.strictEqual(b.lastIndexOf('a', 1), 0);
408assert.strictEqual(b.lastIndexOf('b', 1), 1);
409assert.strictEqual(b.lastIndexOf('c', 1), -1);
410assert.strictEqual(b.lastIndexOf('a', -1), 0);
411assert.strictEqual(b.lastIndexOf('a', -4), 0);
412assert.strictEqual(b.lastIndexOf('a', -b.length), 0);
413assert.strictEqual(b.lastIndexOf('a', -b.length - 1), -1);
414assert.strictEqual(b.lastIndexOf('a', NaN), 0);
415assert.strictEqual(b.lastIndexOf('a', -Infinity), -1);
416assert.strictEqual(b.lastIndexOf('a', Infinity), 0);
417// lastIndexOf Buffer:
418assert.strictEqual(b.lastIndexOf(buf_a), 0);
419assert.strictEqual(b.lastIndexOf(buf_a, 1), 0);
420assert.strictEqual(b.lastIndexOf(buf_a, -1), 0);
421assert.strictEqual(b.lastIndexOf(buf_a, -4), 0);
422assert.strictEqual(b.lastIndexOf(buf_a, -b.length), 0);
423assert.strictEqual(b.lastIndexOf(buf_a, -b.length - 1), -1);
424assert.strictEqual(b.lastIndexOf(buf_a, NaN), 0);
425assert.strictEqual(b.lastIndexOf(buf_a, -Infinity), -1);
426assert.strictEqual(b.lastIndexOf(buf_a, Infinity), 0);
427assert.strictEqual(b.lastIndexOf(buf_bc), 1);
428assert.strictEqual(b.lastIndexOf(buf_bc, 2), 1);
429assert.strictEqual(b.lastIndexOf(buf_bc, -1), 1);
430assert.strictEqual(b.lastIndexOf(buf_bc, -3), 1);
431assert.strictEqual(b.lastIndexOf(buf_bc, -5), 1);
432assert.strictEqual(b.lastIndexOf(buf_bc, -6), -1);
433assert.strictEqual(b.lastIndexOf(buf_bc, NaN), 1);
434assert.strictEqual(b.lastIndexOf(buf_bc, -Infinity), -1);
435assert.strictEqual(b.lastIndexOf(buf_bc, Infinity), 1);
436assert.strictEqual(b.lastIndexOf(buf_f), b.length - 1);
437assert.strictEqual(b.lastIndexOf(buf_z), -1);
438assert.strictEqual(b.lastIndexOf(buf_empty), b.length);
439assert.strictEqual(b.lastIndexOf(buf_empty, 1), 1);
440assert.strictEqual(b.lastIndexOf(buf_empty, b.length + 1), b.length);
441assert.strictEqual(b.lastIndexOf(buf_empty, Infinity), b.length);
442// lastIndexOf number:
443assert.strictEqual(b.lastIndexOf(0x61), 0);
444assert.strictEqual(b.lastIndexOf(0x61, 1), 0);
445assert.strictEqual(b.lastIndexOf(0x61, -1), 0);
446assert.strictEqual(b.lastIndexOf(0x61, -4), 0);
447assert.strictEqual(b.lastIndexOf(0x61, -b.length), 0);
448assert.strictEqual(b.lastIndexOf(0x61, -b.length - 1), -1);
449assert.strictEqual(b.lastIndexOf(0x61, NaN), 0);
450assert.strictEqual(b.lastIndexOf(0x61, -Infinity), -1);
451assert.strictEqual(b.lastIndexOf(0x61, Infinity), 0);
452assert.strictEqual(b.lastIndexOf(0x0), -1);
453
454// Test weird offset arguments.
455// The following offsets coerce to NaN, searching the whole Buffer
456assert.strictEqual(b.lastIndexOf('b', undefined), 1);
457assert.strictEqual(b.lastIndexOf('b', {}), 1);
458
459// The following offsets coerce to 0
460assert.strictEqual(b.lastIndexOf('b', 0), -1);
461assert.strictEqual(b.lastIndexOf('b', null), -1);
462assert.strictEqual(b.lastIndexOf('b', []), -1);
463
464// The following offset coerces to 2, in other words +[2] === 2
465assert.strictEqual(b.lastIndexOf('b', [2]), 1);
466
467// Behavior should match String.lastIndexOf()
468assert.strictEqual(
469  b.lastIndexOf('b', undefined),
470  s.lastIndexOf('b', undefined));
471assert.strictEqual(
472  b.lastIndexOf('b', {}),
473  s.lastIndexOf('b', {}));
474assert.strictEqual(
475  b.lastIndexOf('b', 0),
476  s.lastIndexOf('b', 0));
477assert.strictEqual(
478  b.lastIndexOf('b', null),
479  s.lastIndexOf('b', null));
480assert.strictEqual(
481  b.lastIndexOf('b', []),
482  s.lastIndexOf('b', []));
483assert.strictEqual(
484  b.lastIndexOf('b', [2]),
485  s.lastIndexOf('b', [2]));
486
487// Test needles longer than the haystack.
488assert.strictEqual(b.lastIndexOf('aaaaaaaaaaaaaaa', 'ucs2'), -1);
489assert.strictEqual(b.lastIndexOf('aaaaaaaaaaaaaaa', 'utf8'), -1);
490assert.strictEqual(b.lastIndexOf('aaaaaaaaaaaaaaa', 'latin1'), -1);
491assert.strictEqual(b.lastIndexOf('aaaaaaaaaaaaaaa', 'binary'), -1);
492assert.strictEqual(b.lastIndexOf(Buffer.from('aaaaaaaaaaaaaaa')), -1);
493assert.strictEqual(b.lastIndexOf('aaaaaaaaaaaaaaa', 2, 'ucs2'), -1);
494assert.strictEqual(b.lastIndexOf('aaaaaaaaaaaaaaa', 3, 'utf8'), -1);
495assert.strictEqual(b.lastIndexOf('aaaaaaaaaaaaaaa', 5, 'latin1'), -1);
496assert.strictEqual(b.lastIndexOf('aaaaaaaaaaaaaaa', 5, 'binary'), -1);
497assert.strictEqual(b.lastIndexOf(Buffer.from('aaaaaaaaaaaaaaa'), 7), -1);
498
499// 你好 expands to a total of 6 bytes using UTF-8 and 4 bytes using UTF-16
500assert.strictEqual(buf_bc.lastIndexOf('你好', 'ucs2'), -1);
501assert.strictEqual(buf_bc.lastIndexOf('你好', 'utf8'), -1);
502assert.strictEqual(buf_bc.lastIndexOf('你好', 'latin1'), -1);
503assert.strictEqual(buf_bc.lastIndexOf('你好', 'binary'), -1);
504assert.strictEqual(buf_bc.lastIndexOf(Buffer.from('你好')), -1);
505assert.strictEqual(buf_bc.lastIndexOf('你好', 2, 'ucs2'), -1);
506assert.strictEqual(buf_bc.lastIndexOf('你好', 3, 'utf8'), -1);
507assert.strictEqual(buf_bc.lastIndexOf('你好', 5, 'latin1'), -1);
508assert.strictEqual(buf_bc.lastIndexOf('你好', 5, 'binary'), -1);
509assert.strictEqual(buf_bc.lastIndexOf(Buffer.from('你好'), 7), -1);
510
511// Test lastIndexOf on a longer buffer:
512const bufferString = Buffer.from('a man a plan a canal panama');
513assert.strictEqual(bufferString.lastIndexOf('canal'), 15);
514assert.strictEqual(bufferString.lastIndexOf('panama'), 21);
515assert.strictEqual(bufferString.lastIndexOf('a man a plan a canal panama'), 0);
516assert.strictEqual(-1, bufferString.lastIndexOf('a man a plan a canal mexico'));
517assert.strictEqual(-1, bufferString
518  .lastIndexOf('a man a plan a canal mexico city'));
519assert.strictEqual(-1, bufferString.lastIndexOf(Buffer.from('a'.repeat(1000))));
520assert.strictEqual(bufferString.lastIndexOf('a man a plan', 4), 0);
521assert.strictEqual(bufferString.lastIndexOf('a '), 13);
522assert.strictEqual(bufferString.lastIndexOf('a ', 13), 13);
523assert.strictEqual(bufferString.lastIndexOf('a ', 12), 6);
524assert.strictEqual(bufferString.lastIndexOf('a ', 5), 0);
525assert.strictEqual(bufferString.lastIndexOf('a ', -1), 13);
526assert.strictEqual(bufferString.lastIndexOf('a ', -27), 0);
527assert.strictEqual(-1, bufferString.lastIndexOf('a ', -28));
528
529// Test lastIndexOf for the case that the first character can be found,
530// but in a part of the buffer that does not make search to search
531// due do length constraints.
532const abInUCS2 = Buffer.from('ab', 'ucs2');
533assert.strictEqual(-1, Buffer.from('µaaaa¶bbbb', 'latin1').lastIndexOf('µ'));
534assert.strictEqual(-1, Buffer.from('µaaaa¶bbbb', 'binary').lastIndexOf('µ'));
535assert.strictEqual(-1, Buffer.from('bc').lastIndexOf('ab'));
536assert.strictEqual(-1, Buffer.from('abc').lastIndexOf('qa'));
537assert.strictEqual(-1, Buffer.from('abcdef').lastIndexOf('qabc'));
538assert.strictEqual(-1, Buffer.from('bc').lastIndexOf(Buffer.from('ab')));
539assert.strictEqual(-1, Buffer.from('bc', 'ucs2').lastIndexOf('ab', 'ucs2'));
540assert.strictEqual(-1, Buffer.from('bc', 'ucs2').lastIndexOf(abInUCS2));
541
542assert.strictEqual(Buffer.from('abc').lastIndexOf('ab'), 0);
543assert.strictEqual(Buffer.from('abc').lastIndexOf('ab', 1), 0);
544assert.strictEqual(Buffer.from('abc').lastIndexOf('ab', 2), 0);
545assert.strictEqual(Buffer.from('abc').lastIndexOf('ab', 3), 0);
546
547// The above tests test the LINEAR and SINGLE-CHAR strategies.
548// Now, we test the BOYER-MOORE-HORSPOOL strategy.
549// Test lastIndexOf on a long buffer w multiple matches:
550pattern = 'JABACABADABACABA';
551assert.strictEqual(longBufferString.lastIndexOf(pattern), 1535);
552assert.strictEqual(longBufferString.lastIndexOf(pattern, 1535), 1535);
553assert.strictEqual(longBufferString.lastIndexOf(pattern, 1534), 511);
554
555// Finally, give it a really long input to trigger fallback from BMH to
556// regular BOYER-MOORE (which has better worst-case complexity).
557
558// Generate a really long Thue-Morse sequence of 'yolo' and 'swag',
559// "yolo swag swag yolo swag yolo yolo swag" ..., goes on for about 5MB.
560// This is hard to search because it all looks similar, but never repeats.
561
562// countBits returns the number of bits in the binary representation of n.
563function countBits(n) {
564  let count;
565  for (count = 0; n > 0; count++) {
566    n = n & (n - 1); // remove top bit
567  }
568  return count;
569}
570const parts = [];
571for (let i = 0; i < 1000000; i++) {
572  parts.push((countBits(i) % 2 === 0) ? 'yolo' : 'swag');
573}
574const reallyLong = Buffer.from(parts.join(' '));
575assert.strictEqual(reallyLong.slice(0, 19).toString(), 'yolo swag swag yolo');
576
577// Expensive reverse searches. Stress test lastIndexOf:
578pattern = reallyLong.slice(0, 100000);  // First 1/50th of the pattern.
579assert.strictEqual(reallyLong.lastIndexOf(pattern), 4751360);
580assert.strictEqual(reallyLong.lastIndexOf(pattern, 4000000), 3932160);
581assert.strictEqual(reallyLong.lastIndexOf(pattern, 3000000), 2949120);
582pattern = reallyLong.slice(100000, 200000);  // Second 1/50th.
583assert.strictEqual(reallyLong.lastIndexOf(pattern), 4728480);
584pattern = reallyLong.slice(0, 1000000);  // First 1/5th.
585assert.strictEqual(reallyLong.lastIndexOf(pattern), 3932160);
586pattern = reallyLong.slice(0, 2000000);  // first 2/5ths.
587assert.strictEqual(reallyLong.lastIndexOf(pattern), 0);
588
589// Test truncation of Number arguments to uint8
590{
591  const buf = Buffer.from('this is a test');
592  assert.strictEqual(buf.indexOf(0x6973), 3);
593  assert.strictEqual(buf.indexOf(0x697320), 4);
594  assert.strictEqual(buf.indexOf(0x69732069), 2);
595  assert.strictEqual(buf.indexOf(0x697374657374), 0);
596  assert.strictEqual(buf.indexOf(0x69737374), 0);
597  assert.strictEqual(buf.indexOf(0x69737465), 11);
598  assert.strictEqual(buf.indexOf(0x69737465), 11);
599  assert.strictEqual(buf.indexOf(-140), 0);
600  assert.strictEqual(buf.indexOf(-152), 1);
601  assert.strictEqual(buf.indexOf(0xff), -1);
602  assert.strictEqual(buf.indexOf(0xffff), -1);
603}
604
605// Test that Uint8Array arguments are okay.
606{
607  const needle = new Uint8Array([ 0x66, 0x6f, 0x6f ]);
608  const haystack = Buffer.from('a foo b foo');
609  assert.strictEqual(haystack.indexOf(needle), 2);
610  assert.strictEqual(haystack.lastIndexOf(needle), haystack.length - 3);
611}
612
613// Avoid abort because of invalid usage
614// see https://github.com/nodejs/node/issues/32753
615{
616  assert.throws(() => {
617    const buffer = require('buffer');
618    new buffer.Buffer.prototype.lastIndexOf(1, 'str');
619  }, {
620    code: 'ERR_INVALID_ARG_TYPE',
621    name: 'TypeError',
622    message: 'The "buffer" argument must be an instance of Buffer, ' +
623             'TypedArray, or DataView. ' +
624             'Received an instance of lastIndexOf'
625  });
626}
627